Battery pack

Abstract

To suppress the effect of gases generated from battery cells on battery packs.SOLUTION: A battery pack 1 has a battery module 10 having a plurality of battery cells 100 and a pack housing 20 that houses the battery module 10. The battery module 10 has pathways for the flow of gases generated from at least some of the battery cells 100.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a battery pack. [Background technology]

[0002] In recent years, various battery packs have been developed. A battery pack includes at least one battery module and a housing that houses the battery module. The battery module includes at least one battery cell.

[0003] Patent Documents 1 and 2 describe a battery tray. The battery tray houses a plurality of battery modules, each of which is composed of a plurality of unit cells. The battery tray defines an intake hole for introducing flames, smoke, or gases inside the unit cells.

[0004] Patent Document 3 describes a battery pack. The battery pack includes a plurality of battery cells and a housing that houses the plurality of battery cells. The plurality of battery cells are grouped into a first battery group and a second battery group. The housing has a beam disposed between the first battery group and the second battery group. The housing further has a base plate that defines a discharge path that communicates with the inside of the beam.

[0005] Patent Document 4 describes a power battery system. The power battery system includes a plurality of battery cells, a plurality of side frames, and an air passage cover. The plurality of battery cells are disposed between two side frames. The air passage cover is attached to the outside of the side frames and forms an air passage together with the side frames. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Special Publication No. 2022-516519 [Patent Document 2] Special Publication No. 2022-515552 [Patent Document 3] US Patent Application Publication No. 2022 / 0123423 [Patent Document 4] Special Publication No. 2018-503934 Summary of the Invention [Problem to be solved by the invention]

[0007] In a battery pack, a battery module having multiple battery cells may be housed in a housing. The battery cells constituting the battery module may generate gas when the battery cells generate abnormal heat. If the gas generated from the battery cells accumulates in the battery pack, it may be difficult to suppress the effect of the gas on the battery pack.

[0008] One example of an object of the present invention is to suppress the influence of gas generated from a battery cell on a battery pack. Other objects of the present invention will become apparent from the description of this specification. [Means for solving the problem]

[0009] One aspect of the present invention is as follows. 1. A battery module having a plurality of battery cells; A housing that houses the battery module; Equipped with The battery pack, wherein the battery module has a path for allowing gas generated from at least some of the battery cells to flow. 2. The battery module further includes a plate covering at least a portion of the plurality of battery cells; 2. The battery pack according to claim 1, wherein the plate has the passage. 3. A plurality of the plates cover different portions of the plurality of battery cells; 3. The battery pack according to claim 2, wherein the paths of the multiple plates are in communication with each other. 4. The battery cell includes a gas exhaust section for exhausting the gas, the battery module has a gas inlet for introducing the gas into the path; The battery pack according to any one of 1. to 3., wherein the gas exhaust section and the gas inlet section at least partially face each other. 5. The housing has another passage for flowing the gas; The battery pack according to any one of 1. to 4., wherein the path and the other path are in communication with each other. Effect of the Invention

[0010] According to the above-described aspects of the present invention, the effect of gas generated from the battery cells on the battery pack can be suppressed. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is a top view of the battery pack according to the embodiment. [Diagram 2] FIG. 2 is a perspective view of a battery module according to the embodiment; [Diagram 3] FIG. 2 is a top view of the battery module according to the embodiment. [Figure 4] FIG. 13 is a top view of a battery pack according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, embodiments and modifications of the present invention will be described with reference to the drawings. In all the drawings, similar components are given similar reference numerals and the description will be omitted as appropriate.

[0013] Fig. 1 is a top view of a battery pack 1 according to an embodiment. Fig. 2 is a perspective view of a battery module 10 according to an embodiment. Fig. 3 is a top view of the battery module 10 according to an embodiment. In Fig. 2, a module housing 200, which will be described later, is shown in a see-through state for the sake of explanation. In Fig. 3, a fifth plate 250, which will be described later, has been removed for the sake of explanation.

[0014] In the embodiment, the battery pack 1 is mounted on an automobile. Specifically, the battery pack 1 is mounted between the front and rear wheels of the automobile. Hereinafter, unless otherwise specified, the battery pack 1 will be described as being mounted on an automobile. However, the battery pack 1 can also be applied to applications other than automobiles.

[0015] In each figure, the X direction, the Y direction, and the Z direction are shown for the purpose of explanation. The X direction indicates the front-rear direction of the battery pack 1. The Y direction is perpendicular to the X direction. The Y direction indicates the left-right direction of the battery pack 1. The Z direction is perpendicular to both the X direction and the Y direction. The Z direction indicates the up-down direction of the battery pack 1. The arrows pointing to the X direction, the arrows pointing to the Y direction, and the arrows pointing to the Z direction indicate the front, left, and up directions of the battery pack 1, respectively. In Figs. 1 and 3, the white circle with a black dot indicating the Z direction indicates that the arrow pointing to the Z direction extends from the back of the paper to the front. The relationship between the X direction, the Y direction, and the Z direction and the front-rear direction, left-right direction, and up-down direction of the battery pack 1 is not limited to the example of the explanation according to the embodiment.

[0016] In the embodiment, the front-rear direction, left-right direction, and up-down direction of the battery pack 1 are determined by the automobile in which the battery pack 1 is mounted. The X direction, Y direction, and Z direction respectively indicate the front-rear direction, left-right direction, and up-down direction of the automobile. The arrow indicating the X direction, the arrow indicating the Y direction, and the arrow indicating the Z direction respectively indicate the front, left, and up directions of the automobile. However, the relationship between the front-rear direction, left-right direction, and up-down direction of the battery pack 1 and the front-rear direction, left-right direction, and up-down direction of the automobile is not limited to this example.

[0017] Hereinafter, as necessary, the side pointed to by an arrow indicating the X direction will be referred to as the +X side, and the side opposite the side pointed to by the arrow indicating the X direction will be referred to as the -X side. Hereinafter, as necessary, the side pointed to by an arrow indicating the Y direction will be referred to as the +Y side, and the side opposite the side pointed to by the arrow indicating the Y direction will be referred to as the -Y side. Hereinafter, as necessary, the side pointed to by an arrow indicating the Z direction will be referred to as the +Z side, and the side opposite the side pointed to by the arrow indicating the Z direction will be referred to as the -Z side.

[0018] The battery pack 1 will be described with reference to FIG.

[0019] The battery pack 1 includes a plurality of battery modules 10 and a pack housing 20 .

[0020] In the embodiment, four battery modules 10 are arranged in two rows and two columns in the X direction and the Y direction. Hereinafter, as necessary, the battery module 10 located on the +X side and the +Y side among the four battery modules 10 will be referred to as a first battery module 10a, the battery module 10 located on the -X side and the +Y side among the four battery modules 10 will be referred to as a second battery module 10b, the battery module 10 located on the +X side and the -Y side among the four battery modules 10 will be referred to as a third battery module 10c, and the battery module 10 located on the -X side and the -Y side among the four battery modules 10 will be referred to as a fourth battery module 10d. However, the number and arrangement of the battery modules 10 are not limited to those described in the embodiment.

[0021] The pack housing 20 houses a plurality of battery modules 10. Specifically, the pack housing 20 has a bottom plate 22, a frame 24, and a top plate (not shown). In the example shown in FIG. 1, the bottom plate 22 has a substantially rectangular plate shape having a pair of sides parallel to the X direction and another pair of sides parallel to the Y direction when viewed from the Z direction. However, the shape of the bottom plate 22 is not limited to the shape shown in FIG. 1. The plurality of battery modules 10 are disposed on the surface side of the bottom plate 22 on the +Z side. The frame 24 is disposed on the surface side of the bottom plate 22 on the +Z side. When viewed from the Z direction, the frame 24 at least partially surrounds a space in which the plurality of battery modules 10 are accommodated. Hereinafter, as necessary, the space surrounded by the frame 24 when viewed from the Z direction is referred to as the accommodation space of the pack housing 20. In the example shown in FIG. 1, when viewed from the Z direction, the frame 24 has a substantially rectangular frame shape having a pair of sides parallel to the X direction and another pair of sides parallel to the Y direction. However, the shape of the frame 24 is not limited to the shape shown in FIG. 1. The top plate covers the multiple battery modules 10 from the +Z side.

[0022] Each battery module 10 will be described with reference to FIGS.

[0023] The battery module 10 includes a plurality of battery cells 100 and a module housing 200 .

[0024] The multiple battery cells 100 are stacked in the Y direction. Hereinafter, as necessary, the multiple battery cells 100 stacked in the Y direction will be referred to as a stack of battery cells 100. The dimension of each battery cell 100 in the X direction is the dimension in the longitudinal direction of each battery cell 100. The dimension of each battery cell 100 in the Z direction is the dimension in the lateral direction of each battery cell 100. The dimension of each battery cell 100 in the Y direction is the dimension in the thickness direction of each battery cell 100. The shape of each battery cell 100 is not limited to this example.

[0025] Each battery cell 100 includes a battery element 110, a pair of terminals 120, a pair of cover materials 130, and an exterior film 140. In Fig. 3, the battery element 110 and the pair of cover materials 130 present inside the exterior film 140 are illustrated by dashed lines.

[0026] The battery element 110 has a substantially rectangular parallelepiped shape. The dimension of the battery element 110 in the X direction is the dimension in the longitudinal direction of the battery element 110. The dimension of the battery element 110 in the Z direction is the dimension in the lateral direction of the battery element 110. The dimension of the battery element 110 in the Y direction is the dimension in the thickness direction of the battery element 110. The shape of the battery element 110 is not limited to this example.

[0027] The battery element 110 has at least one positive electrode (not shown), at least one negative electrode (not shown), and at least one separator (not shown). For example, a plurality of positive electrodes and a plurality of negative electrodes are alternately stacked in the Y direction. At least a portion of the separator is located between the positive electrodes and the negative electrodes adjacent in the Y direction. For example, each of a plurality of sheet-like separators may be located between the positive electrodes and the negative electrodes adjacent in the Y direction. Alternatively, one sheet-like separator may be in a zigzag shape passing through the region between the positive electrodes and the negative electrodes adjacent in the Y direction. Alternatively, the positive electrode, the negative electrode, and the separator may be wound so that the separator is disposed between the positive electrode and the negative electrode. In one example, the positive electrode, the negative electrode, and the separator are wound in a state where both sides of one of the positive electrode and the negative electrode are covered by the separator. In another example, a laminate including a plurality of unit laminates including a positive electrode, a separator, and a negative electrode in this order may be wound. However, the winding structure of the positive electrode, negative electrode, and separator is not limited to these examples.

[0028] The battery cell 100 may be an all-solid-state battery. In an all-solid-state battery, a solid electrolyte layer is provided in a portion corresponding to a separator. An all-solid-state battery does not contain an electrolyte. Hereinafter, unless otherwise specified, the battery cell 100 will be described as a battery cell containing an electrolyte.

[0029] The pair of terminals 120 are located on both sides of the battery element 110 in the X direction. Each terminal 120 is a conductor such as a metal. One of the pair of terminals 120 and the positive electrode of the battery element 110 are electrically connected to each other. The other of the pair of terminals 120 and the negative electrode of the battery element 110 are electrically connected to each other. Thus, the polarities of the pair of terminals 120 of each battery element 110 are different from each other.

[0030] The pair of lid members 130 cover both end faces of the battery element 110 in the X direction. Each lid member 130 is, for example, a resin body. When viewed from the X direction, each lid member 130 has a substantially rectangular shape having a pair of short sides parallel to the Y direction and a pair of long sides parallel to the Z direction. The +X side terminal 120 at least partially protrudes toward the +X side from the +X side surface of the +X side lid member 130 when the +X side lid member 130 covers the +X side end face of the battery element 110. The -X side terminal 120 at least partially protrudes toward the -X side from the -X side surface of the -X side lid member 130 when the -X side lid member 130 covers the -X side end face of the battery element 110.

[0031] Each cover member 130 includes a valve 132. The valve 132 is located on the +Z side with respect to the terminal 120. However, the position where the valve 132 is provided is not limited to this example. When abnormal heat generation occurs in the battery cell 100, gas may be generated from inside the battery cell 100. For example, when abnormal heat generation occurs in the battery cell 100, gas may be generated from the battery element 110 or the electrolyte inside the battery cell 100. When gas is generated from inside the battery cell 100, the valve 132 opens and can discharge the gas from inside the battery cell 100 to the outside of the battery cell 100. Thus, the valve 132 serves as a gas discharge section for discharging the gas generated from inside the battery cell 100. In one example, the valve 132 is formed by partially thinning the thickness of the cover member 130. However, the structure of the valve 132 is not limited to this example.

[0032] The exterior film 140 is wrapped around the battery element 110 and the pair of lid members 130 in the X direction. The outer peripheral surface around the X direction of the lid member 130 on the +X side and the inner peripheral surface around the X direction of the end of the exterior film 140 on the +X side are joined to each other by a joining method such as heat fusion. The outer peripheral surface around the X direction of the lid member 130 on the -X side and the inner peripheral surface around the X direction of the end of the exterior film 140 on the -X side are joined to each other by a joining method such as heat fusion. Parts of the exterior film 140 are joined to each other by a joining method such as heat fusion at least in part around the X direction of the battery element 110. Thus, the battery element 110 is sealed by the exterior film 140.

[0033] The multiple battery cells 100 are electrically connected in series, in parallel, or in a combination of series and parallel.

[0034] An example in which a plurality of battery cells 100 are connected in series will be described. In this example, the polarities of the +X side terminals 120 of the battery cells 100 adjacent in the Y direction are different from each other, and the polarities of the -X side terminals 120 of the battery cells 100 adjacent in the Y direction are different from each other. The plurality of battery cells 100 are connected in series in order from the battery cell 100 at one end in the Y direction to the battery cell 100 at the other end in the Y direction, with the +X side terminals 120 of the battery cells 100 adjacent in the Y direction electrically connected to each other via a bus bar (not shown) or the -X side terminals 120 of the battery cells 100 adjacent in the Y direction electrically connected to each other via a bus bar (not shown).

[0035] An example will be described in which a plurality of battery cells 100 are connected in parallel. In this example, the +X side terminals 120 of the plurality of battery cells 100 have the same polarity, and the -X side terminals 120 of the plurality of battery cells 100 have the same polarity. The plurality of battery cells 100 are connected in parallel with the +X side terminals 120 of the plurality of battery cells 100 electrically connected to each other via a bus bar (not shown), and with the -X side terminals 120 of the plurality of battery cells 100 electrically connected to each other via a bus bar (not shown).

[0036] An example will be described in which a plurality of battery cells 100 are connected in series and parallel in combination. In this example, a stack of battery cells 100 includes a plurality of cell groups, each including at least two battery cells 100 connected in parallel via a bus bar (not shown). A method for connecting at least two battery cells 100 in parallel in each cell group can be the same as a method for connecting a plurality of battery cells 100 in parallel. A plurality of cell groups are connected in series via a bus bar (not shown). A method for connecting a plurality of cell groups in series can be the same as a method for connecting a plurality of battery cells 100 in series.

[0037] The module housing 200 houses a stack of battery cells 100. The module housing 200 includes a first plate 210, a second plate 220, a third plate 230, a fourth plate 240, a fifth plate 250, and a sixth plate 260. Each plate is made of a material with relatively high heat resistance, such as a metal.

[0038] 2, when viewed from the X direction, each of the first plate 210 and the second plate 220 has a generally rectangular plate shape having a pair of long sides parallel to the Y direction and a pair of short sides parallel to the Z direction. The first plate 210 covers a portion of the stack of battery cells 100 on the +X side. The second plate 220 covers a portion of the stack of battery cells 100 on the -X side. The shapes of the first plate 210 and the second plate 220 are not limited to the shape shown in FIG.

[0039] 2, when viewed from the Y direction, each of the third plate 230 and the fourth plate 240 has a generally rectangular plate shape having a pair of long sides parallel to the X direction and a pair of short sides parallel to the Z direction. The third plate 230 covers a portion of the stack of battery cells 100 on the +Y side. The fourth plate 240 covers a portion of the stack of battery cells 100 on the -Y side. The shapes of the third plate 230 and the fourth plate 240 are not limited to the shape shown in FIG. 2.

[0040] As shown in FIG. 2, when viewed from the Z direction, each of the fifth plate 250 and the sixth plate 260 has a substantially rectangular plate shape having a pair of short sides parallel to the X direction and a pair of long sides parallel to the Y direction. However, the shape of the fifth plate 250 and the sixth plate 260 is not limited to the shape shown in FIG. 2. For example, when viewed from the Z direction, each of the fifth plate 250 and the sixth plate 260 may have a substantially rectangular plate shape having a pair of long sides parallel to the X direction and a pair of short sides parallel to the Y direction. Alternatively, when viewed from the Z direction, each of the fifth plate 250 and the sixth plate 260 may have a substantially square plate shape having a pair of sides parallel to the X direction and another pair of sides parallel to the Y direction. The fifth plate 250 covers a portion of the stack of the battery cells 100 on the +Z side. The sixth plate 260 covers a portion of the stack of the battery cells 100 on the -Z side.

[0041] The module housing 200 has a gas path for flowing gas generated from at least some of the battery cells 100. In the embodiment, each of the first plate 210, the second plate 220, the third plate 230, and the fourth plate 240 defines a hollow internal space. This internal space of each of the first plate 210, the second plate 220, the third plate 230, and the fourth plate 240 serves as a gas path of the module housing 200.

[0042] As shown in FIG. 3, the -X side surface of the first plate 210 defines a plurality of first module gas introduction holes 212. The plurality of first module gas introduction holes 212 and the gas path inside the first plate 210 are in communication with each other. Therefore, the gas discharged from the valve 132 of the cover member 130 on the +X side of each battery cell 100 can enter the gas path inside the first plate 210 through the plurality of first module gas introduction holes 212. Therefore, each first module gas introduction hole 212 serves as a gas introduction part for introducing the gas generated from the battery cell 100 into the gas path inside the first plate 210. In the embodiment, each first module gas introduction hole 212 and each valve 132 on the +X side are at least partially opposed to each other in the X direction. Therefore, compared to a case where the first module gas introduction holes 212 and the +X side valves 132 do not face each other in the X direction, it is possible to make it easier for gas generated from the +X side valves 132 to enter the gas path inside the first plate 210. However, the number and arrangement of the first module gas introduction holes 212 are not limited to the number and arrangement according to the embodiment.

[0043] As shown in FIG. 3, the surface on the +X side of the second plate 220 defines a plurality of second module gas introduction holes 222. The plurality of second module gas introduction holes 222 and the gas path inside the second plate 220 are in communication with each other. Therefore, the gas discharged from the valve 132 of the lid member 130 on the -X side of each battery cell 100 can enter the gas path inside the second plate 220 through the plurality of second module gas introduction holes 222. Therefore, each second module gas introduction hole 222 serves as a gas introduction part for introducing the gas generated from the battery cell 100 into the gas path inside the second plate 220. In the embodiment, each second module gas introduction hole 222 and each valve 132 on the -X side are at least partially opposed to each other in the X direction. Therefore, compared to a case where the second module gas introduction holes 222 and the -X side valves 132 do not face each other in the X direction, it is possible to make it easier for the gas generated from the -X side valves 132 to enter the gas path inside the second plate 220. However, the number and arrangement of the second module gas introduction holes 222 are not limited to the number and arrangement according to the embodiment.

[0044] The gas paths inside the first plate 210, the second plate 220, the third plate 230, and the fourth plate 240 are mutually connected. Therefore, gas can flow between the first plate 210, the second plate 220, the third plate 230, and the fourth plate 240. Specifically, the gas path inside the first plate 210 and the gas path inside the third plate 230 are mutually connected via a plurality of first communication holes 202a provided at the end of the first plate 210 on the +Y side and the end of the third plate 230 on the +X side. The gas path inside the first plate 210 and the gas path inside the fourth plate 240 are mutually connected via a plurality of second communication holes 202b provided at the end of the first plate 210 on the -Y side and the end of the fourth plate 240 on the +X side. The gas path inside the second plate 220 and the gas path inside the third plate 230 are connected to each other via a plurality of third communication holes 202c provided at the end of the second plate 220 on the +Y side and the end of the third plate 230 on the -X side. The gas path inside the second plate 220 and the gas path inside the fourth plate 240 are connected to each other via a plurality of fourth communication holes 202d provided at the end of the second plate 220 on the -Y side and the end of the fourth plate 240 on the -X side. The number and arrangement of the first communication holes 202a, the second communication holes 202b, the third communication holes 202c, and the fourth communication holes 202d are not limited to the number and arrangement shown in FIG. 2 and FIG. 3.

[0045] As shown in Fig. 2 and Fig. 3, a plurality of first gas exhaust parts 214 are provided on the surface of the +X side of the first plate 210. Each of the first gas exhaust parts 214 defines a gas exhaust port that opens toward the +X side. Each of the first gas exhaust parts 214 exhausts gas from a gas path inside the first plate 210 through the gas exhaust port. As shown in Fig. 2, in the embodiment, four first gas exhaust parts 214 are provided at four corners of the surface of the +X side of the first plate 210 as viewed from the X direction. However, the number and arrangement of the first gas exhaust parts 214 are not limited to the number and arrangement shown in Fig. 2 and Fig. 3.

[0046] 3, a plurality of second gas exhaust parts 224 are provided on the -X side surface of the second plate 220. Each second gas exhaust part 224 defines a gas exhaust port that opens toward the -X side. Each second gas exhaust part 224 exhausts gas from a gas path inside the second plate 220 through the gas exhaust port. In the embodiment, four second gas exhaust parts 224 are provided at four corners of the -X side surface of the second plate 220 when viewed from the X direction. However, the number and arrangement of the second gas exhaust parts 224 are not limited to the number and arrangement shown in FIG.

[0047] A method for discharging gas generated from at least some of the battery cells 100 to the outside of the battery pack 1 will be described with reference to FIG. 1, and with reference to FIG. 2 and FIG. 3 as necessary.

[0048] The pack housing 20 has a gas path for flowing gas generated from at least some of the battery cells 100. In the embodiment, the frame 24 defines a hollow internal space. This internal space of the frame 24 serves as a gas path of the pack housing 20. As shown in FIG. 1, the pack housing 20 has a pair of pressure relief valves 26. The pair of pressure relief valves 26 are provided on the outer surface of the frame 24 on the -X side. Gas in the gas path inside the pack housing 20 is discharged to the outside of the battery pack 1 via the pair of pressure relief valves 26. However, the number and arrangement of the pressure relief valves 26 are not limited to the number and arrangement shown in FIG. 1.

[0049] In the embodiment, the gas path inside the module housing 200 of each battery module 10 and the gas path inside the pack housing 20 are directly connected without passing through the storage space of the pack housing 20. This makes it possible to prevent the gas generated from the battery cells 100 from accumulating in the storage space of the pack housing 20. The gas generated from the battery cells 100 may be at a relatively high temperature. Therefore, if the gas generated from the battery cells 100 accumulates in the storage space of the pack housing 20, the battery pack 1 may be affected by the gas. In contrast, in the embodiment, the effect of the gas generated from the battery cells 100 on the battery pack 1 can be suppressed.

[0050] As shown in FIG. 1, in the embodiment, the gas path inside the first battery module 10a and the gas path inside the second battery module 10b are directly connected to each other via the second gas exhaust part 224 on the -X side of the first battery module 10a and the second module gas introduction hole 222 on the +X side of the second battery module 10b. Therefore, the gas generated from the battery cell 100 of the first battery module 10a can flow to the gas path inside the second battery module 10b via the gas path inside the first battery module 10a. Similarly, the gas generated from the battery cell 100 of the second battery module 10b can flow to the gas path inside the first battery module 10a via the gas path inside the second battery module 10b. The same applies to the gas path inside the third battery module 10c and the gas path inside the fourth battery module 10d.

[0051] As shown in FIG. 1, in the embodiment, the gas path inside the first battery module 10a and the gas path inside the pack housing 20 are directly connected to each other via the first module gas introduction hole 212 on the +X side of the first battery module 10a. Therefore, the gas generated from at least one of the battery cells 100 of the first battery module 10a and the second battery module 10b can flow to the gas path inside the pack housing 20 without passing through the storage space of the pack housing 20. Therefore, it is possible to prevent the gas generated from at least one of the battery cells 100 of the first battery module 10a and the second battery module 10b from being discharged to the storage space of the pack housing 20. The same applies to the gas path inside the third battery module 10c and the gas path inside the pack housing 20.

[0052] As shown in FIG. 1, in the embodiment, the gas path inside the second battery module 10b and the gas path inside the pack housing 20 are directly connected to each other via the second gas exhaust part 224 on the -X side of the second battery module 10b. Therefore, the gas generated from at least one of the battery cells 100 of the first battery module 10a and the second battery module 10b can flow to the gas path inside the pack housing 20 without passing through the storage space of the pack housing 20. Therefore, it is possible to prevent the gas generated from at least one of the battery cells 100 of the first battery module 10a and the second battery module 10b from being discharged to the storage space of the pack housing 20. The same applies to the gas path inside the fourth battery module 10d and the gas path inside the pack housing 20.

[0053] The relationship between the gas path inside each battery module 10 and the gas path inside the pack housing 20 is not limited to the relationship according to the embodiment. For example, the gas path inside the first battery module 10a and the gas path inside the third battery module 10c may be connected to each other. Similarly, the gas path inside the second battery module 10b and the gas path inside the fourth battery module 10d may be connected to each other. The gas path inside the first battery module 10a and the gas path inside the pack housing 20 may be directly connected to each other, for example, via a gas exhaust part arranged on the +Y side of the first battery module 10a. The same applies to the second battery module 10b. The gas path inside the third battery module 10c and the gas path inside the pack housing 20 may be directly connected to each other, for example, via a gas exhaust part arranged on the -Y side of the third battery module 10c. The same applies to the fourth battery module 10d.

[0054] 4 is a top view of a battery pack 1A according to a modified example. The battery pack 1A according to the modified example is similar to the battery pack 1 according to the embodiment, except for the following points.

[0055] The battery pack 1A according to the modified example includes a plurality of battery modules 10A and a pack housing 20A. In the modified example, four battery modules 10A are lined up in the X direction. However, the number and arrangement of the battery modules 10A are not limited to the number and arrangement shown in FIG. 4. Each battery module 10A includes a plurality of battery cells 100, a first plate 210A, and a second plate 220A. The pack housing 20A according to the modified example includes a bottom plate 22A, a frame 24A, and a pair of pressure release valves 26A.

[0056] The multiple battery cells 100 of each battery module 10A are stacked in the Y direction. As in the embodiment, hereinafter, the multiple battery cells 100 stacked in the Y direction in each battery module 10A according to the modified example will be referred to as a stack of battery cells 100 as necessary. The dimension of each battery cell 100 in the X direction is the dimension in the longitudinal direction of each battery cell 100. The dimension of each battery cell 100 in the Z direction is the dimension in the lateral direction of each battery cell 100. The dimension of each battery cell 100 in the Y direction is the dimension in the thickness direction of each battery cell 100. The shape of each battery cell 100 is not limited to this example.

[0057] The first plate 210A according to the modified example covers the +X side portion of the stack of battery cells 100. The second plate 220A according to the modified example covers the -X side portion of the stack of battery cells 100.

[0058] Similar to the battery module 10 according to the embodiment, the battery module 10A according to the modification has a gas path for flowing gas generated from at least some of the battery cells 100. Specifically, similar to each of the first plate 210 and second plate 220 according to the embodiment, each of the first plate 210A and second plate 220A according to the modification defines a hollow internal space, and this internal space of each of the first plate 210A and second plate 220A serves as a gas path for the battery module 10A.

[0059] Gas in the gas path inside the first plate 210A is exhausted from gas exhaust ports provided on both end faces in the Y direction of the first plate 210A. The gas exhaust ports provided on both end faces in the Y direction of the first plate 210A penetrate both end faces in the Y direction of the first plate 210A in the Y direction. Therefore, the rigidity of the first plate 210A can be improved compared to a case in which the gas exhaust ports penetrate the +X side surface of the first plate 210A in the X direction.

[0060] Gas in the gas path inside the second plate 220A is exhausted from gas exhaust ports provided on both end faces in the Y direction of the second plate 220A. The gas exhaust ports provided on both end faces in the Y direction of the second plate 220A penetrate both end faces in the Y direction of the second plate 220A in the Y direction. Therefore, the rigidity of the second plate 220A can be improved compared to a case in which the gas exhaust ports penetrate the -X side surface of the second plate 220A in the X direction.

[0061] A pair of first pack gas introduction holes 24aA is provided on both sides in the Y direction of each first plate 210A on the inner surface around the Z direction of the frame 24A according to the modified example. Gas discharged from the gas exhaust ports on both end surfaces in the Y direction of the first plate 210A enters the gas path inside the frame 24A through the pair of first pack gas introduction holes 24aA. Gas in the gas path inside the frame 24A is discharged to the outside of the battery pack 1A through the pair of pressure release valves 26A.

[0062] A pair of second pack gas introduction holes 24bA are provided on both sides in the Y direction of each second plate 220A on the inner surface around the Z direction of the frame 24A according to the modified example. Gas discharged from the gas exhaust ports on both end surfaces in the Y direction of the second plate 220A enters the gas path inside the frame 24A through the pair of second pack gas introduction holes 24bA. Gas in the gas path inside the frame 24A is discharged to the outside of the battery pack 1A through the pair of pressure release valves 26A.

[0063] In the modified example, the gas exhaust port at both end faces in the Y direction of the first plate 210A and the pair of first pack gas introduction holes 24aA on both sides in the Y direction of the first plate 210A of the frame 24A are at least partially opposed in the Y direction. Similarly, the gas exhaust port at both end faces in the Y direction of the second plate 220A and the pair of second pack gas introduction holes 24bA on both sides in the Y direction of the second plate 220A of the frame 24A are at least partially opposed in the Y direction. Thus, the gas path inside the first plate 210A and the gas path inside the frame 24A are mutually connected. Similarly, the gas path inside the second plate 220A and the gas path inside the frame 24A are mutually connected. Thus, it is possible to make it difficult for the gas generated from the battery cell 100 to remain in the storage space of the pack housing 20A. Therefore, in the modified example, it is possible to suppress the influence of the gas generated from the battery cell 100 on the battery pack 1A.

[0064] Although the embodiment and modified examples of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various configurations other than those described above can also be adopted. [Explanation of symbols]

[0065] 1,1A battery pack, 10,10A battery module, 10a first battery module, 10b second battery module, 10c third battery module, 10d fourth battery module, 20,20A pack housing, 22,22A bottom plate, 24,24A frame, 24aA first pack gas inlet, 24bA second pack gas inlet, 26,26A pressure release valve, 100 battery cell, 110 battery element, 120 terminal, 130 cover material, 132 valve, 140 exterior film, 200 module housing, 202a first communication hole, 202b second communication hole, 202c third communication hole, 202d fourth communication hole, 210,210A first plate, 212 first module gas inlet, 214 first gas exhaust section, 220,220A second plate, 222 Second module gas inlet, 224 second gas outlet, 230 third plate, 240 fourth plate, 250 fifth plate, 260 sixth plate

Claims

1. A battery module having a plurality of battery cells; A housing that houses the battery module; Equipped with The battery pack, wherein the battery module has a path for allowing gas generated from at least some of the battery cells to flow.

2. The battery module further includes a plate covering at least a portion of the plurality of battery cells; The battery pack of claim 1 , wherein the plate includes the passage.

3. a plurality of the plates covering different portions of the plurality of battery cells; The battery pack of claim 2 , wherein the passages of the plurality of plates are in communication with one another.

4. the battery cell includes a gas exhaust portion for exhausting the gas, the battery module has a gas inlet for introducing the gas into the path; The battery pack according to any one of claims 1 to 3, wherein the gas discharge section and the gas introduction section are at least partially opposed to each other.

5. the housing has another passage for the flow of the gas; The battery pack according to any one of claims 1 to 3, wherein the path and the other path are in communication with each other.

Images